Brush having adjustable hardness

ABSTRACT

Brush having adjustable hardness includes a bristle plate, a perforated disc member and a cover member located adjacent the bristle plate at opposite sides thereof, means for adjusting the perforated disc member in position relative to the bristle plate, the adjusting means including an externally threaded pin and an internally threaded hollow shaft substantially centrally located on one of the members, respectively, and threadedly engageable with one another through a substantially central opening formed in the bristle plate.

United States Patent 1191 Weihrauch Mar. 5, 1974 [54] BRUSH HAVING ADJUSTABLE HARDNESS 2,854,684 10/1958 Hardman ct al. I/193 I 3,612,705 /1971 Duval 401/75 [75] Invent g Aschbach 3,678,529 7/1972 Woods et al /180 erman y FOREIGN PATENTS OR APPLICATIONS [73] Assgnee' cm'onet'werke Hemmh schlerf 1,229,982 12 1966 Germany 15/187 GmbH Odenw Germany 81 l/1886 Great Britain 15/169 22 Filed; Man 27 1972 17,421 12/1915 Great Britain 337,349 5/1959 Switzerland 21 Appl. No.2 238,496

Primary ExaminerPeter Feldman [30] Foreign Application Priority Data Attorney, Agent, or Firm-I-Ierbert L. Lerner Mar. 25, 1971 Germany 2114533 ABSTRACT 52 us. (:1 ..15/169, 15/160 15/176 Brush having adjustable hardness includes a bristle 51 Int. Cl. A46b 17/06, Ai6b 9/08 P Perforated disc member and a cover member [58] Field of searchum 15/159 160 168 169 176 located adjacent the bristleplate at opposite sides 15/184 186 187 188 thereof, means for adjusting the perforated disc mem- 401/75, g 2 her in position relative to the bristle plate, the adjusting means including an externally threaded pin and an [56] References Cited internally threaded hollow shaft substantially centrally located on one of the members, respectively, and UNITED STATES PATENTS threadedly engageable with one another through a 29 g substantially central opening formed in the bristle zln a 1,205,894 11/1916 Hilfiker 15/188 x plate 1,735,802 11/1929 Statuto 15/ 176 12 Claims, 8 Drawing Figures 4 rq Z/ /1 7 M Q 5 1 W 2 1 QJMULLW BRUSH HAVING ADJUSTABLE HARDNESS The invention relates to a brush having adjustable hardness, and more particularly to a massage brush which includes a bristles carrier, a perforated disc, cover and an optional handle, the perforated disc being adjustable relative to the bristles carrier.

The purpose of producing a massage brush having adjustable hardness lies in the ability of the user thereof to change the effective length of the bristles as required. The effect thereof is that the bristle length is changeable continously from short, hard bristles to long, soft bristles and, depending upon the parts of the skin to be treated, the brushing can be gentle or rough.

The advantages of such a brush are, of course, also applicable to corresponding constructions of both cleaning and household brushes as well as to brooms.

The adjustability in hardness of the effective bristle length gains importance as the service life of the bristle material increases. Only in view of the high quality of synthetic fibers is the additional cost of the adjusting mechanism worthwhile because the better brushing effect attained can be utilized over a longer period of time.

In order to attain greater stiffness of the bristles, it has been known heretofore to vary the effective length of the bristles by means of a perforated plate which is adjustably disposed between the bristles carrier and a particular location along the length of the bristles.

It has been found to be a disadvantage of the heretofore known constructions of brushes having variable hardness that the mechanism for adjusting the hardness of the brush is of too complex construction, the adjustment is too sensitive or too gross and cannot be lockedin at a selected position of the perforated disc or does not meet the requirements for practical operation.

In heretofore known massage brushes having a handle, the handle is secured force-lockingly in a slot, mostly of dovetail cross section. This type of attachment for the handle is unreliable, because the handle either loosens and comes out too easily, or it is stuck too tightly. If the connection is too loose, there is, in fact, danger of injury to the user resulting from the sharp edges of the dovetail profile of the handle.

It is accordingly an object of the invention to provide a brush, such as a massage brush or similar brush, having adjustable hardness which avoids the foregoing disadvantage of heretofore known brushes of this-general type and which, moreover, has an adjusting mechanism of which only a few elements are accommodated in the brush housing.

A further object of the invention is to provide such a brush which affords an easy and convenient manual adjustment of the effective bristle length and, simultaneously, satisfactory locking at the selected bristle length.

With the foregoing and other objects in view, there is provided in accordance with the invention, a brush having adjustable hardness, comprising a bristle plate, a perforated disc member and a cover member located adjacent the bristle plate at opposite sides thereof, means for adjusting the perforated disc member in position relative to the bristle plate, the adjusting means comprising an externally threaded pin and an internally threaded hollow shaft substantially centrally located on one of the members, respectively, and threadedly engageable with one another through a substantially central opening formed in the bristle plate.

In accordance with another feature of the invention, the cover is provided with a web disposed transversely thereon and formed with recesses at both ends thereof and the handle is formed with two projections disposed respectively opposite to one another in longitudinal direction and received in the respective recesses.

, In accordance with a further feature of the invention, there is provided a non-releasable connection between the cover and the bristle carrier comprising a collar formed at the outer wall of the hollow shaft, and a plurality of pins firmly secured to and extending from the bristles carrier, the pins having respective portions thereof radially inwardly bent substantially at right angles, the portions of the pins being snappable behind the collar.

In order to prevent canting of the perforated disc during the adjustment thereof and in order to achieve a positive parallel guidance of the perforated disc relative to the surface of the bristle carrier, in accordance with an added feature of the invention, three pins are disposed in spaced relationship about a circle coaxial to the threaded pin and guided in correspondingly disposed openings formed in the bristles carrier.

In accordance with yet another feature of the invention, there are provided means for locking the perforated disc between the cover and the bristles carrier comprising a brake toothing formed of small teeth or a knurl located at mutually engaging surfaces of the cover and the bristles carrier.

In accordance with an additional feature of the invention, there are provided means for limiting relative motion between the cover and the bristles carrier comprising a respective pin secured to and extending from the cover and the bristle carrier, respectively and disposed at equal radial distances, respectively, from the common center of rotation thereof, so as to be in abut ting engagement with one another after the cover and the bristles carrier have been turned at most one time relative to one another about the common center of rotation.

In accordance with another feature of the invention, the ends of the bristles have a rounded shape to improve the massaging effect thereof.

In accordance with a further feature of the invention, the ends of the bristles define a zig-zag profile.

Other features which are considered as characteristic for the invention are set forth in the appended claims.

Although the invention is illustrated and described herein as embodied in brush having adjustable hardness, it is nevertheless not intended to be limited to the details shown, since various modification and structural changes may be made therein without departing from the spirit of the invention and within the scope and range of equivalents of the claims.

The construction and method of the invention, however, together with additional objects and advantages thereof will be best understood from the following description of specific embodiments when read in connection with the accompanying drawings, in which:

FIG. 1 is an exploded longitudinal sectional view of the massage brush of the invention;

FIG. 2 is a side elevational view of the cover forming part of the inventive massage brush as viewed from the right-hand side of FIG. 1;

FIG. 3 is a front elevational view of the cover forming part of FIG. 1;

FIG. 4 is a longitudinal sectional view, partly diagrammatic, of the brush of FIG. 1 provided with snapon handle according to the invention;

FIG. 5 is a bottom plan view of the snap-on handle of FIG. 4;

FIG. 6 is an enlarged diagrammatic fragmentary view of a detail of the brush enclosed in the circle D in FIG. 4, showing bristles with rounded ends;

FIG. 7 is a modified form of the massage brush wherein the bristles define a zig-zag outline; and

FIG. 8 is a bottom plan view of another embodiment of the invention showing the array of bristles studded on the brush and defining a zig-zag outline from two directions.

Referring now to the drawing, and first, particularly to FIG. 1 thereof, there is shown therein a massage brush according to the invention, and having as main parts thereof, a cover 1, a bristles carrier 2 and a perforated disc 3. The perforated disc 3 is provided with three pins 8, which are disposed on a circle concentric to the threaded post 6, and secured to the disc 3. The pins 8 are guidable by the threaded post 6 into openings formed in the bristles carrier 2. By rotating the cover I, the perforated disc 3 is raised and lowered for adjusting the bristles 7 to a desired effective length s. The raising and lowering of the perforated disc 3 is effected by a screw connection between a hollow shaft 5 formed at the underside of the cover 1 and provided with an internal thread, and the externally threaded post 6 which is centrally secured to the perforated disc 3 and is in threaded engagement with the hollow shaft 5. A nondetachable connection of all three main parts I, 2 and 3 of the brush of the invention, is obtained by providing four pins 13, which are mounted or formed on the bristles carrier 2, with portions thereof bent inwardly at right angles, by which the pins 13 snap in behind a collar 12 which is formed on the outer wall surface of the hollow shaft 5. The perforated disc 3 is arrested to a given extent in a selected position by the intermeshing of small teeth 14 and 15 formed on the periphery of the cover 1 and the bristles plate or carrier 2.

A limit to the rotation of the cover 1 is effected by pins 10 and 11 which extend, respectively, from the bristles carrier 2 and the cover 1.

The construction of the cover 1 for the attachment of a handle 17 is seen in FIGS. 2, 3 and 4. A web 4 which is raised above the surface of the cover is formed with recesses 16 at both ends thereof. By flattening the cover 1 at the rim thereof, an enlargement of the Web 4 is formed which provides a good finger grip for turning the cover 1. The basic form of the handle 17 is constructed according to FIGS. 4 and 5, as a hollow U- shaped profile which matches the dimensionsfo the web 4. At one end thereof, snap-in elements are provided which are bent away at right angles from the central web 21 and form cam projections 18 and 19, the projections 19 at the handle side being formed at a resilient strap 20 which is of narrow construction as compared to the central web 21. By bending the strap 20 upwardly, as viewed in FIG. 4, the projections 18 and 19 can be permitted to snap into the recesses 16 of the massage brush and can clamp it force-lockingly as well as form-lockingly.

FIG. 6 is an enlarged fragmentary view of FIG. 4 showing a bundle of bristles with rounded bristle ends 7 A particular embodiment of a massage brush shown in FIG. 7 has bristles that are provided with a so-called zig-zag cut 22.

When the zig-zag cut 22 according to FIG. 7 is applied in two directions at right angles to each other, pyramidal, tapered bristle cusps 23 are produced as shown in the embodiment of FIG. 8.

The bristle ends of an array of bristles provided with a zig-zag cut 22 can also be rounded.

The advantages obtained with the invention are, in particular, that a usable massage brush, whose bristles can conveniently be adjusted in hardness and can be locked effectively so as to maintain that selected hardness, is producible with few individual parts such as a cover, a bristles carrier, a perforated disc and an optimal handle, each of which may be formed of injectionmolded integral members and are therefore not subjected to the danger of corrosion when used in water.

A further advantage of the invention of thisapplication is that by providing a web at the cover, good manipulation or handling for turning as well as a good possibility for clamping the cover in a positive forcelocking and form-locking manner by means of a handle are afforded.

I claim:

1. Brush having adjustable hardness, comprising a bristle plate, a perforated disc member and a cover member located adjacent said bristle plate at opposite sides thereof, said perforated disc member and said cover member being formed with mutually cooperating means for adjusting said perforated disc member in position relative to said bristle plate, said adjusting means comprising an externally threaded pin and an internally threaded hollow shaft integral with and substantially centrally located on and extending from one of said members, respectively, and threadedly engageable with one another through a substantially central opening formed in said bristle plate.

2. Brush according to claim 1 including a web disposed transversely on said brush and formed with recesses at both ends thereof.

3. Brush according to claim 2 including a handle formed with two projections disposed respectively opposite to one another in longitudinal direction of the handle and receivable in the respective recesses formed in said web.

4. Brush according to claim 1 including a nonreleasable connection between said cover and said bristle plate comprising a collar formed at the outer surface of said hollow shaft, and a plurality of pins firmly secured to and extending from said bristle plate, said pins having respective portions thereof, radially inwardly bent substantially at right angles, said portions of said p'ins being snappable behind said collar.

5. Brush according to claim 1 including three additional pins disposed in spaced relationship about a circle coaxial to said threaded pin and guided in correspondingly disposed openings formed in said bristle plate.

6. Brush according to claim 1 including brake toothing located between said cover member and said bristle plate.

7. Brush according to claim 6 wherein said brake toothing is formed of small teeth located at mutually engaging surfaces of said cover member and said bristle plate.

8. Brush according to claim 6 wherein said brake toothing is formed of a knurl located at mutually engaging surfaces of said cover member and said bristle plate.

limiting relative motion between said cover member and said bristle plate comprising a respective pin secured to and extending from said cover member and 9. Brush according to claim 1 including means for forming pyramidal cusps. sssssssssssss 

1. Brush having adjustable hardness, comprising a bristle plate, a perforated disc member and a cover member located adjacent said bristle plate at opposite sides thereof, said perforated disc member and said cover member being formed with mutually cooperating means for adjusting said perforated disc member in position relative to said bristle plate, said adjusting means comprising an externally threaded pin and an internally threaded hollow shaft integral with and substantially centrally located on and extending from one of said members, respectively, and threadedly engageable with one another through a substantially central opening formed in said bristle plate.
 2. Brush according to claim 1 including a web disposed transversely on said brush and formed with recesses at both ends thereof.
 3. Brush according to claim 2 including a handle formed with two projections disposed respectively opposite to one another in longitudinal direction of the handle and receivable in the respective recesses formed in said web.
 4. Brush according to claim 1 including a non-releasable connection between said cover and said bristle plate comprising a collar formed at the outer surface of said hollow shaft, and a plurality of pins firmly secured to and extending from said bristle plate, said pins having respective portions thereof, radially inwardly bent substantially at right angles, said portions of said pins being snappable behind said collar.
 5. Brush according to claim 1 including three additional pins disposed in spaced relationship about a circle coaxial to said threaded pin and guided in correspondingly disposed openings formed in said bristle plate.
 6. Brush according to claim 1 including brake toothing located between said cover member and said bristle plate.
 7. Brush according to claim 6 wherein said brake toothing is formed of small teeth located at mutually engaging surfaces of said cover member and said bristle plate.
 8. Brush according to claim 6 wherein said brake toothing is formed of a knurl located at mutually engaging surfaces of said cover member and said bristle plate.
 9. Brush according to claim 1 including means for limiting relative motion between said cover member and said bristle plate comprising a respective pin secured to and extending from said cover member and said bristle plate, respectively.
 10. Brush according to claim 1 wherein the bristles are formed with rounded ends.
 11. Brush according to claim 1 wherein the ends of the bristles define a zig-zag profile.
 12. Brush according to claim 1 wherein the ends of the bristles define a zig-zag profile in two directions transversely to one another, the ends of the bristles forming pyramidal cusps. sssssssssssss 